Form: Frame Assignment - Hinges
A frame hinge assignment consists of a hinge property and a location for that hinge along the frame object. The location is specified as a relative distance along the full length of the object measured from the i-end. The relative distance is equal to the distance from the i-end of the object to the hinge location, divided by the length of the frame object. Hinges may not be located within the end offsets. If the specified relative distance places a hinge within an end offset, the hinge is automatically moved to the inside face of that offset.
Assign nonlinear hinges to frame objects assigned frame section properties as follows:
Select the frame objects to which the assignment is to be made.
Select the Assign menu > Frame > Hinges command to access the Frame Assignment - Hinges form.
If a single object is selected before implementing this command, the form displays the currently assigned hinges, if any.
If multiple elements were selected before implementing this command:
If all objects have the same hinge assignments, the form displays those assignments.
If the objects have no assignments or do not share a common hinge assignment, the form is essentially empty.
Add, modify, or delete a hinge assignment as follows:
Add a hinge assignment.
Select an Auto or user defined hinge property from the Hinge Property drop-down list.
Type a location in the Relative Distance edit box. The relative distance is measured from End I (the start) of the frame object. The range is from zero to one. When end offsets are defined, if the relative distance is specified such that the hinge falls within an end offset, the program automatically moves the hinge to the inside face of the end offset. The hinges are always located within the clear length of the object between the end offsets.
Click the Add button.
Note: If the Auto option is selected from the Hinge Property drop-down list, the Auto Hinge Assignment Data form will display when the Add button is clicked. Use that form to specify the Auto Hinge Type based on tables in ASCE 41-13 or Buckling Restrained Brace specifications.
Also, when an Auto hinge type definition is highlighted in the Hinge Property drop-down list on the Frame Assignment - Hinges form, the Auto Hinge Assignment Data area will display key parameters of the hinge definition. In addition, the Modify/Show Auto Hinge Assignment Data button will become available. Clicking that button will display the Auto Hinge Assignment Data form.
Modify an existing hinge assignment. Modify the location of a hinge on the selected object(s) as follows:
Select the hinge in the Hinge Property/Relative Location list box.
Edit the location in the Relative Distance edit box.
Click the Modify button.
Delete an existing hinge assignment.
Highlight the previously assigned hinge property in the Frame Hinge Assignment Data list box.
Click the Delete button.
Click the OK button to complete the assignment.
Multiple nonlinear hinges can be assigned to the same frame object. In addition, multiple hinges can be assigned at the same location. However, this may make it difficult to interpret some of the results.
See Also
Load Case Data - Nonlinear Modal History (FNA)